Determine the internal forces at point $J$ for the structure shown, where member $BD$ can only carry axial forces. Take the dimension $a=180mm$ and the

external load $P=420N.$

axial force:

$F_J=$

$($tolerance $1N,$ magnitude only$)$

shear force:

$S{F}_J=$

$($tolerance $1N,$ magnitude only$)$

bending moment:

$B{M}_J=$

$($tolerance $100N^{**}mm,$ magnitude only$)$